According to the latest Health Survey for England, 65% of men and 58% of women are either overweight or obese. Photograph: Dominic Lipinski/PA

Waistlines have expanded so much that two-thirds of men and almost as many women are now overweight, according to an NHS report that has prompted fresh calls for action against obesity. In England 24% of men and 26% of women in England are obese, while 65% of men and 58% of women are either overweight or obese.

Dr Aseem Malhotra, a cardiologist who recently examined the extent of obesity as part of an inquiry by the Academy of Medical Royal Colleges, said the figures were the worst for British obesity he had seen.

"It's absolutely shocking that 65% of men and 58% of women have a dangerously unhealthy weight. The biggest explanation for this trend is our obesgenic food environment – the oversupply of cheap, sugary food", said Malhotra, who works at a London hospital.

Overweight is defined as having a body mass index (BMI) of between 25 and 29, while someone with a BMI of 30 or more is classed as obese. BMI is calculated as someone's weight in kilograms divided by the square of their height in metres. Doctors and health ministers say that people should try to maintain a normal weight, which is a BMI of between 18.5 and 24, in order to minimise their risk of weight-related illness.

The figures, which provide the starkest illustration yet of the increasing normalisation of unhealthy weight, are contained in the latest edition of the Health Survey for England, a massive research exercise commissioned by the NHS's Health and Social Care Information Centre every year to map changing trends in health. Based on interviews with 8,610 adults and 2007 children during 2011, it is regarded as in-depth and authoritative.

When the report was first carried out in 1993, only 13% of men and 16% of women were classed as obese.

"England already has some of the highest rates of obesity in the developed world. These findings highlight the need to be food aware and honest about our eating habits," said Anna Soubry, the public health minister.

But the survey does offer some tentative hope that the gradual but largely unbroken growth in obesity may be slowing after almost two decades. "The rate of increase in obesity prevalence has been slower in the second half of the period than the first half, and there are indications that the trend may be flattening out over recent years," it said. But obesity in women in 2011 was the highest since 1993, it added.

Soubry said that the coalition had helped encourage a much wider use of labels on foodstuffs so consumers could choose healthier options.

Ministers will be launching a new campaign early next year to encourage people to eat more healthily, she added. But Malhotra said that regulation, notably a crackdown on "unregulated marketing" by food companies, to discourage consumption of unhealthy products, was needed.